For LCD panels, a layer of thin film material is formed on each array substrate and color filter substrate. Such layers are used to drive liquid crystal molecules between the array substrate and the color filter substrate to be aligned in a certain direction, and are called “alignment film.” The alignment film is generally made of polyimide (PI), and is typically classified to include a photo-alignment type PI film and a rubbing alignment type PI film. However, no matter whether the alignment film is a photo-alignment type PI film or a rubbing alignment type PI film, formation of them have disadvantages. First, formation of rubbing alignment type PI film would be likely to generate dust particles, residual electrostatic charges, and rubbing marks, which will further result in low yield of manufactured LCD panels. Formation of photo-alignment type PI film can prevent these problems from occurring. However, due to poor thermal stability and aging resistance of photo-alignment type PI film, and its unfavorable anchoring action for liquid crystal molecules, formation of photo-alignment type PI film in LCD panels affects display quality of LCD panels. Secondly, the PI material itself is highly polar and tends to absorb water, and thus the PI material deteriorates during storage and transportation thereof. This leads to expensive prices of the PI material.
In case PI films are omitted in structures of LCD panels, the liquid crystal molecules cannot be aligned vertically. Although there is an alternative to use a self-alignment liquid crystal material, which is mixed with the liquid crystal molecules, where a vertical alignment agent of the self-alignment liquid crystal material is adsorbed on the array substrate to drive the liquid crystal molecules to align vertically, adsorption ability of the vertical alignment agent onto the substrate is weak, and thus alignment of the liquid crystal molecules is unsatisfactory. Therefore, there is a need to provide a method for manufacturing a liquid crystal display panel to solve the above-mentioned problems.